Vapor electric apparatus.



PATENTED MAR. 24, 1908.

0. 0. KRUH.

VAPOR ELECTRIC APPARATUS.

APPLICATION FILED OGT.1B 1905.

2 SHBETSr-SHEET 1.

Inventor Osias O. Kruh,

y fitty.

Witnesses:

Fig.

Fig. 3.

Witnesses PATENTBD MAR. 24, 1908- 0. 0. KRUH.

VAPOR ELECTRIC APPARATUS.

APPLIOATION nun 0011a. 1006.

2 sums-sum z.

Osias O. Kruh,

UNITED sTArns r ENT OFFICE.

OSIAS O. KRUH, OI SCHENEC'IADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRICCOMPANY, A CORPORATION OF NEW YORK.

' VAPOR ELECTRIC APPARATUS.

Specification of Letters Patent.

Patented March 24, 1908.

Application filed October 18, 1905. Serial No. 283,258.

To all whom it may concern:

Be it known that I, OSIAS O. linen, a subject of the Emperor ofAustria-Hungary, residing at Schenectady, county of Schenectady, andState of New York, have invented certain new and useful Improvements inVapor Electric Apparatus, of which the following is a specification.

My resent invention relates to apparatus in which electric discharges orarcs take place in evacuated inclosures, and more particularly toapparatus using alternating current as a source of current supply.

The invention may be embodied in devices of this character used asrectifiers, lamps or the like, and embodies various novel features ofconstruction as pointed out more particularly inthe appended claims.

The invention itsell, however, will be better understood by reference tothe following description taken in connection with the accompanyingdrawings in which Figure 1 represents one embodiment of my invention;Fig. 2 a detail, and Figs. 3 and 4 modified forms of my invention.

In vapor electric devices, so called because the arcs therein aremaintained through the medium of a vapor, a plurality of anodes areusually employed where the apparatus is to be used in connection. with asource of alternating current sup ly. These anodes constitute thetermina s of electric arcs which play between the res ective anodes anda common ne ativc e ectrode or cathode.

Under certam conditions of operation it.

sometimes happens that an arc takes place from anode to anode, therebyforming a short circuit, which though momentary may be sullicientlyviolent, or if often repeated, to injure or destroy the a paratus. lovercome this trouble by provning the anodes with shields which directthe arc stream emanating from the cathode in a manner to protect theanodes from any s )attering or other emission of nercury from thecathode, of which material the cathode is usually composed, and whichserve also to protect the anodes from any other radiation or emanationfrom the cz-rthodc. The shields are also arranged to protect the anodesfrom. any dropping of globules oi condensed mercury-taking place in theevacuated inclosure in which the anodes are located.

In Fig. 1, I have represented a mercury vapor rectifier for changingalternating current into direct current. The rectifiertube consists ofan exhausted receptacle 1, generally of glass, which "tube is providedwith suitable electrodes. The positive electrodes or anodes areindicated at 2 and 3 and may be formed of cylinders or plates, or othersuitable shapes, of artificial graphite, titanium carbid, iron, or thelike. Current is conveyed to each electrode by means of leadingin wireswhich pass through the wall ofthe receptacle 1. hi the case of the anode2, the leading-in wire, usually of platinum, is shown at 4 and is sealedthrough the inner end of a reentrant portion 5 of the tube 1. Theportion of the wire 4 extending between the anode and the reentrantmember 5 is 'surrounded by a coating of vitreous material 5, such aslava, hard glass, or the like. The shieldstor the anode 2 may, ofcourse, vary widely in form and still retain their essential functions.The present arrangement, however, consists of an inner shield 6 and anouter shield 7. This shield 6 is a tube of glass or the like, the lowerend of which may be sealed about the part 5, while the upper end extendsover and beyond the anode. 2 and is closed. An opening 8, however, isformed in the side of the tubular shield 6, which serves as a passagefor the are stream going to the anode 2. The outer shield '7 surroundsthe shield 6 and is conveniently arranged concentric therewith. Thisshield is closed at the top as indicated, and may be.

sealed at its bottom portion about the part 5 by which it, as well asthe inner shield 6 'is supported. An o'ening 9 into the outer shleld 7is provider near the lower end'there of and preferably at the side 0posite, the anode 3 which cooperates with t e anode 2. The anode3 isprovided with shields 10 and 11 substantially the same in constructionand arrangement as the shields 6 and 7. Thus no special description ofthese shields is necessary.

The negative electrode or cathode with which the anodes 2 and 3cooperates, con sists of a body of mercury 12 located in a pocket formedin the lower end of the tube 1. A leading-in wire 13 serves as usual toconvey current flowing between this electrode and an outside circuit. Astarting anode, which like the electrode 12 is of mercury, is providedfor starting the apparatus into operation in the usual manner. ing intothe small pocket or chamber con- The opentaining the mercuryconstituting the starting electrode, is shown in Fig. 1 'at 14, whilethe de ending portion of the pocket is indicate ingdottedlines. Thisstarting electrode and the pocket containing it is, however, shownbetter by'the detail view in Fig.

rectly to alternating current supply mains such as 16 and 17. Inductancecoils 18 and 19 are joined in series across these mains. The junctionpoint 20 between them we tends to a consumption circuit 21, the otherterminal of which is connected to the oathode 12. For the purpose ofstarting the rectifier the starting anode 13 is connected through aresistance or other current limiting device 22 to one of the supplyleads.

By shaking or tiltingthe apparatus so as to bring the mercury of theelectrodes 12 and 15. into momentary contact, a starting arc ensueswhich when the current is in the proper direction, causes the main arcsto start between the cathode and the main anodes 2 and 3. A number, oftrials may perhaps benecessary in some cases before the apparatusstarts, as the direction of current may not at the'first trial be suchas required. When the apparatus is in operation the arc stream from thecathode 12goes to each of the anodes 2 and 3 and before reaching thecorresponding anode it is constrained to follow a path which bends onitself. Thus the arc stream from the cathode 12 passesinto the opening 9and then up through the tubular assage afforded between the concentricwal s of the shields 6 and 7 and then into the opening 8 in the innershield 6 through which it passes to the anode 2. The arc stream as itpasses to the opening 9 is of the nature of a high velocity blast whichnecessarily carries along with it more or less imperfectly vaporizedmercury. The greater portion of this superfluous matter is thrown off bythe arc stream as it turns into the opening 9. As the arc streamcontinues farther and then again changes its direction to pass into theopening 8 any remaining superfluous mercury is likewise projected beyondthe opening by its momentum. The anode is thereby effectually protectedfrom any spattering or other emanation from the cathode. Moreover it isrotected also from any falling drops or globu es of mercury which maydescend from the walls of the tube 1, as the mercury vapor generated inthe apparatus is condensed. Also the anode is protected from the effectof any radiation, perhaps in the nature of ultra violet rays, emanatingfrom the cathode surface. This protection is afforded by the interposedwalls of the two glass shields 6 and 7. The whole arrangement thusconstitutes a most effective means for preventing arcing between anodes.

I have indicated in passing, some of the causes which I believe areactive in producing arcing between anodes. I do not wish to beconsidered as guaranteeing the accuracy of what from my observations Inow consider to be the most likely causes of the arcing, since thebeneficial effects of my in vention may be obtained, regardless of thereasons therefor, by following the modes of construction which I havepointed out.

Instead of using the apparatus shown in Fig. 1 I may use an arrangementsomewhat as shown in Fig. 3. In this figure I have shown merely therectifier tube without indicating the connections of such tube to itselectric circuits, as such connections are well understood. In Fig. 3,the evacuated receptacle is indicated at 23. The graphite anodes areshown at 24 and 25 and the cooperating cathode at 26. The anodes are asbefore surrounded by cylinders 26 and 27 closed at both ends andsupported in any suitable manner as from the leading-in conductors ofthe respective anodes. Communication with the anode is afforded in thecase of the cylinder 26 by an opening 27 formed in the upper portion ofthe cylindrical wall and on that side of the cylinder away from theanode 25. A cylindrical shield 28, closed at the top and open at thebottom, is mounted concentrically over the inner shield 26 and may beconveniently supported from a small standard 29 extending from theclosed top of the inner shield 26 as indicated. The other anode 25 islikewise provided with an outer shield 30 mounted and arranged in thesame manner as the shield for the anode 24, so that no furtherdescription thereof is necessary. In either case the outer shields28-and 30, in addition to serving as an additional safe guard to protectthe anodes against contact with falling or otherwise projected particlesof mercury, serves also to direct the arcstream passing from the cathodeto the anode. The walls of the shield 28 for example constrain the arcstream to pass in a direction tangential tothe inner shield 26 andthereby prevents. superfluous matter, and particularly condensedmercury, from entering the opening 27 into the inner shield 26surrounding the anode 24. The momentum acquired by the particles as theyare carried along in the arc stream causes them to be projected past theopening 27 so that only that portion of the arc stream enters which isnecessary as a vehicle for conveying current.

Still another arrangement of the protect-- ing shields may be employedas indicated in Fig. 4. In this figure the evacuated receptacle of therectifier is indicated at 31.

I by a number of openings such as at 36, 37

and the like, located about the sides of the shield as indicated.

The inner shield 35 is closed at its top and open at the bottom andsurrounds the anode 32. It may conveniently be supported by a small rod38 of glass or the like depending from the inner side of the top of theshield 34. The cooperating anode 33 is provided with similarlyconstructed and arranged shields 39 and which re uire no specialdescription. The are from t e cathode 34 enters the openings 36, 37 andthe like, then passes down between the walls of the shields 34 and 35and then up through the open bottom of the shield 35 to the anode 32.The are stream is thereby effectually freed from any superfluous matterand the danger from arcing, due to contact'of such matter with theanode, is thus obviated. The. anode moreover is also well protectedagainst contact with the mercury condensing and falling Within therectifier tube.

The devices shown in this application are covered broadly by the claimsin my application Serial No. 194,520 filed February 20,

\ 1904, which is now involved in interferences. This present caseislimited to'the improvements on the invention of said formerapplication which are herein described and.

claimed, and the claims herein are therefore not to be construed ascovering anything disclosed in my said rior ap lication.

It is evident t at various modifications may be made in .the embodimentof my invention without departing from the spirit thereof, for whichreason I do not wish to be limited to the details shown and. described.

What I claim as new and desire to secure by Letters Patent'of the UnitedStates, is

1. The combination of a receptacle or container, electrodes therein, andshields therefor arranged one inside of the other.

2. The combination of a receptacle or container, electrodes therein, andshields for said electrodes having non-registering openings therein.

3. The combination of a rece tacle or container, a vaporizable electrodet erein, a plu rality of cooperating electrodes, and shields for each ofsaid cooperating electrodes, the shields for each electrode beinglocated one inside the other.

4. The combinationof a rece tacle or container, electrodes therein, ands ields for one at least of said electrodes, said shields being arrangedone about the other and rovided with openings located to produce a cange in direction of the arc stream going to the electrode.

In witnesswhereof, I have hereunto set my hand this'17'th day ofOctober, 1905.

' OSIAS O. K'RUH. Witnesses:

BENJAMIN B. HULL, HELEN ORFORD.

